Non-aqueous electrolyte batteries are used for various types of applications utilizing their characteristics such as high capacity and high voltage. Particularly in recent years, the demand for non-aqueous electrolyte batteries for vehicle application has increased in accordance with the implementation of electric vehicles and the like.
Non-aqueous electrolyte batteries for vehicle application are mainly applied to driving power sources of motors of electric vehicles, but other applications are also being developed. For example, emergency reporting systems for making reports to parties concerned when a vehicle accident or the like has occurred are currently being developed, and research is being conducted on the application of non-aqueous electrolyte batteries as a power source of such systems.
Such systems operate only in limited circumstances in actuality, but it is necessary that they reliably operate at the time of an emergency. Thus, batteries functioning as the power source are required to have reliability in that their characteristics can be satisfactorily maintained even after long-term storage. Accordingly, for such applications, non-aqueous electrolyte primary batteries are used that have better storage characteristics than those of non-aqueous electrolyte secondary batteries that are widely used as power sources of electronic devices, namely batteries whose capacity is unlikely to decrease even after long-term storage of several years or more.
As negative electrode active materials for the non-aqueous electrolyte primary batteries, metallic lithium or a lithium alloy such as a Li—Al (lithium-aluminum) alloy is used. Since a lithium alloy can also be used as a negative electrode active material in non-aqueous electrolyte secondary batteries, a proposal has been made to stabilize battery characteristics by forming a negative electrode using a clad material of a metal capable of absorbing and releasing lithium and a dissimilar metal incapable of absorbing and releasing lithium (Patent Document 1).